Method of and apparatus for lifting oils



' Nb'v. 1, 1927.

a. A. KRAMER METHOD OF AND APPARATUS F08 LIFTING OILS Filed July 6. 1925l umR 1 QQO IIII/ i'llllll II/III. v

Gasmv A. KRAMER, a8?- Patented Nov. 1, 1927.

UNITED STATES PATENT OFFICE.

GUSTAV A. KRAMER, OIEv CONCORD, CALIFORNIA, ASSIGNOR, BY MESNEASSIGNMENTS,

T SDIIPLEX REFI'NING COMPANY, OF SAN FRANCISCO, CALIFORNIA, A. CORPORA-TION OF CALIFORNIA.v

IMIEITHOID OIE'JANT) APPARATUS FOR LIETIN G OILS..'

Applicationfll'ed July 6,1925. Serial No. 41,573.

My invention relates to the art of oil refining and more particularly toa novel means of raising oil from one level to another, and it has apeculiar utility in lubrlcating oil refining plants operating under highvacuum. The handling of 0118 1n vacuum plants by mechanical pumpspresents certain difficulties especially since it is extremely hardto'keep'packed joints tight when pumping liquid at 'the'hightemperatures used in such plants, and some leakage through such jointsmay be anticipated.

" In lubricating oil plants operating under high vacuum any such leakageis especially l5 objectionable since it results in the vacuum pullingair into the system. Many lubricating oil plants are operated atabsolute pressures below 25 millimetersof mercury and even relativelsmall amounts of air leaking into such a p ant not only combine with theoil to produce objectionable compounds 1n the oil but also producegaseous products which have a large volume due to the low absolutepressure.v Since .the gaseous products are not condensible but must beremoved by the vacuum pumps, this necessitateslarge pumps and makes itdiflicult to maintain the vacuum. V

It is an object of the present invention to provide means to lift 011from one level to another without the use of mechanically operatingpumps, and with the practical certainty that no air will be introducedinto the oil as it is lifted even when the oil is subjected to hightemperatures and extremely low absolute pressures.

This is accomplished by maintaining a static head on the lower end ofthe column of oil which is to be lifted and by lightening the column ofoil by injecting therein a material which is in the gaseous state at thetemperature and pressure maintained insaid column, this material beinginjected either as a liquid or a vapor. This admixture of gas lightensthe average specific gravity of the column and allows the static head toforce the oil therein to flow upwardly. Obviously the material usedmustnot have an injurious effect on' the oil and should prefer ably bechemically inert with relation tothe oil.

It is a further object of the invention. to provide means by which hotoil may be readily pumped, the term hot oil being a temperature of useas a lifting medium a material which assumes a gaseous or more properlya vapor state at the temperature and pressure in they column but whichisof such a nature that it may be readily condensed and withdrawn as a,liquid.

Fortunately we have available a material which is particularly suitablefor this purpose, and in the practical operation of the invention, whenused to liftoil in a vacuum lubricating oil refining plant, steam ispreferably used since it is inert with relation to the oil, is a gas atthe temperature and pressure at which the oil is refined, and is readilycondensible. Other vapors such as those of gasoline or other lighthydrocarbons might be used, but in practice steam is usually preferable.

Further objects and advantages will be made evident hereinafter.

Referring to the drawing which is for illustrative purposes only,

Fig. 1 illustrates a portion of a battery of Olll stills equipped withmy invention, the various elements of the apparatus being old inltlheart and being illustrated diagrammatica y.

Fig. 2 is a section through the steam injection nozzle used in myinvention.

In the apparatus illustrated in the draw ing I show a pair of stills 10and 11 which may be part of a battery of such devices. I also show aheater 12, a separator 13. and a vacuum producing apparatus 14. Thestills 10 and 11 maybe cylindrical or spherical and are preferablyprovided with domes 20 and 21. Oil is delivered to the still 10 througha p pe 22 having a valve 23, vapor being taken from the top of the stillthrough a pipe 24. The pipe 24 leads to the vacuum producing device 14which may consist of a separating chamber 25 into which the vapor isconducted, this chamber 25 being provided with a spray-nozzle 26 throughwhich water is forced from a pipe 27 having a a coil of pipe 44 thereinand a heating device such as an oil burner 42 which is controlled by avalve 43. In the coil 44 of the heater 12 the oil may be heatedand'delivered to a feeder this feeder consisting of a long pipeextending downwardly and connecting at its lower end 51 with a riser 52.A jacket 53 surrounds the riser 52 near its lower end, the riser beingperforated inside the jacket 53 as shown at 54 in Fig. 2. Steam isdelivered to the jacket 53 through a pipe 55 controlled by a valve 56,the steam mixing with the oil in the riser and moving upwardly therewithinto the separator 13.

The separator 13 may beof any convenient form suitable to separateliquid from a mixture of steam, oil and gases. The separated liquid isdelivered from the bottom of the separator into a pipe having twobranches and 61, the branch 60 having a valve 62 and the branch 61having a. valve 63. The branch 60 communicates with the dome 20 of thestill 10 and the branch 61 communicates with the dome 21 of the still11. The top of the separator is connected by a pipe 65 with the pipe 24.The dome 21 is connected through a pipe 66 with the pipe 24. The still11 is provided with an outlet pipe 67 having a Valve 68.

The method of operation is as follows:

The still 10 being charged through the pipe 22, the vale 23 may beclosed and a vacuum may be drawn on the still by the use of the pump 32,the valves 28 and 68 being closed. The oil tends to flow downwardlythrough the pipe 40 into the feeder 50 through the furnace 12. Steambeing injected through the openings 54 into the riser 52 tends'to causethe oil to flow therein due to an unbalanced pressure between the feeder50 and the riser 52. The fluid in the riser 52 containing a large numberof. bubbles of steam has a much smaller unit weight than the liquid inthe feeder 50 and there is a consequent downward flow through the feeder50 and an upward flow through the riser 52. The steam acting upon theoil in the riser 52 tends to promote a distillation thereof. In theseparator 13 any steam and uncondensed gas or vapors are separated fromthe oil. which may be returned throughthe valve 62 and the branch 60 tothe still 10. It is obviously possible by continuing the injection ofsteam to cause the oil to continuously circulate outwardly through thepipe 40 and back to the still through the branch 60. The oil is heat.-ed in the furnace 12 by means of externally applied heat and ismaintained at such temperature that no condensation of steamoc ours inthe riser 52.

The lubricating oil vapors are withdrawn through the pipe 24 and arecondensed in the chamber 25 by means of the water spray 26. The -still10 may also be externally heated. After the distillation has proceededto a certain degree it is sometimes desired to transfer the charge fromthe still 10 into the still 11, which can be readily accomplished byclosing the valve 62 and openin the valve 63. Due to the lifting action0 the steam injected into the riser 52, the oil is withdrawn from thestill 10 through the pipe 40 and is passed through the heater 12 to thefeeder 50 passing upwardly through the riser 52 into the separator 13.In the separator 13 the oil is freed from gas, steam and other vaporsand is delivered through the valve 63 to the branch 61 into the still11. In the still 11 the distillation may be continued.

It will be noted that by the use of the riser 52 into which I injectsteam, I am able to provide for a flow of hot oil either from the still10 through the'heater 12 and back to the still 10, or from the still 10through the heater 12 to the still 11. The use of steam in this manneris particularly advantageous in vacuum distillation, in which thepresence of steam is highly desirable. It may be also accomplished withan extremely small weight of steam due to the large volume of the steamat the temperatures employed in the vacuum distillation of lubricatingoil and the high vacuums maintained therein.

In practice I may maintain the space 25 atan absolute pressure as low as25 mm. of mercury and the temperature of the oil in the stills 10 and 11may be in excess of 300 F. At these high vacuums and high temperaturesit is extremely difficult to circulate oil using mechanical pumps, andmy invention provides a ready means for elevating hot oil from one levelto another, or for circulating it through any desired piece ofapparatus. I claim as my invention:

1. An apparatus for moving hot oils from a lower to a higher level whichcomprises:

a feeder conducting oil downwardly from said lower, level forestablishing a static head; a riser connected at its lower end to thelower end of said feeder; means for introducing steam into said risernear the lower end thereof; and means for maintaining the fluids in saidriser at such a tempera ture and pressure that no condensation of saidsteam occurs therein.

2. An apparatus for moving hot. oils from a lower to. a higher levelwhich comprises: a feeder conducting oil downwardly from said lowerlevel for establishing a static head; a

' is chemically inert with relation to said oil fluids in said riser atsuch a temperature and pressure that no condensation of said vaporoccurs therein.

3. A method of feeding oil into an enclosed space maintained under lowabsolute pressure which comprises: maintaining a body of oil to providea static head; establishing a vertical column of oil having its lowerend in communication with said body of oil so that said column isbalanced against said static head; injecting a material, which and whichis a vapor at the temperature and pressure prevailing in said space anda liquid at normal atmospheric temperature and pressure, into the lowerend of said column in suflicient quantities to lighten the column to asufiicient degree to permit said static head to force the upper end ofsaid column into said space; separating the vapor from the oil in saidspace; removing said vapor from said space and cooling it under lowabsolute pressure to produce a condensate; and removing fluids from saidspace to maintain the desired low absolute pressure in said space.

4. A method of feeding oil into an enclosed space maintained under lowabsolute pressure, which comprises: maintaining a body of oil to providea static head; estab lishing a column having its lower end incommunication with said body of oil so that said column is balancedagainst said static head; injecting steam into the lower end of saidcolumn which is maintained at a .temperature and pressure suflicient tomaintain said steam in vapor form, said steam being injected in aquantity suflicient to lighten the column to such a degree-as to permitthe static head to force oil from the upper end of said column into saidspace;-separating the steam from the oil and cooling it under lowabsolute pressure to produce water; and removing fluids from said spaceand connected spaces in sufiicient quantities to maintain the desiredlow absolute pressure.

5. A method of establishing an upward movement of hot oil in a columnextending from a lower point to a higher point which comprises:establishing an impelling static head on the lower end of said column bysupplying hot oil under pressure to said lower end; lowering thespecific gravity of said column by injecting therein a material,chemically inert with relation to the oil, which is a vapor at thepressure and temperature prevailing in said column, said material beinginjected in amounts sufficient to lighten the column to a degree thatwill cause said static head to force said oil out of the top of saidcolumn into an enclosedspace; separating the oil and vapor in saidspace; and condensing said vapor in said space.

6. A method of lifting oil into an enclosed space maintained under apartial vacuum which comprises: maintaining a body of oil to provide astatic head; establishing a column of oil having its lower end incommunication with said body of oil; injecting into the lower part ofsaid column a material which is a vapor at the temperature and pressureof said column but which is readily condensible at the pressure andtemperature in said space, said material being injected in suflicientquantities to lighten the column and permit said static head to forcethe upper end of said column into said-space: separating the vapor fromthe'oil in said space; and thereafter condensing and removing saidmaterial as a liquid.

In testimony whereof, I have-hereunto set my hand at Martinez,California, this 29th day of June, 1925.

GUSTAV A. KRAMER.

